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PS(1) Linux User's Manual PS(1)

NAME

ps - report a snapshot of the current processes.

SYNOPSIS

ps [options]

DESCRIPTION

ps displays information about a selection of the active processes. If

you want a repetitive update of the selection and the displayed

information, use top(1) instead.

This version of ps accepts several kinds of options:

1 UNIX options, which may be grouped and must be preceded by a dash.

2 BSD options, which may be grouped and must not be used with a dash.

3 GNU long options, which are preceded by two dashes.

Options of different types may be freely mixed, but conflicts canappear. There are some synonymous options, which are functionally

identical, due to the many standards and ps implementations that this

ps is compatible with.

Note that "ps -aux" is distinct from "ps aux". The POSIX and UNIX

standards require that "ps -aux" print all processes owned by a user

named "x", as well as printing all processes that would be selected by

the -a option. If the user named "x" does not exist, this ps may

interpret the command as "ps aux" instead and print a warning. This

behavior is intended to aid in transitioning old scripts and habits. It

is fragile, subject to change, and thus should not be relied upon.

By default, ps selects all processes with the same effective user ID

(euid=EUID) as the current user and associated with the same terminal

as the invoker. It displays the process ID (pid=PID), the terminal

associated with the process (tname=TTY), the cumulated CPU time in

[dd-]hh:mm:ss format (time=TIME), and the executable name (ucmd=CMD).

Output is unsorted by default.

The use of BSD-style options will add process state (stat=STAT) to the

default display and show the command args (args=COMMAND) instead of the

executable name. You can override this with the PS_FORMAT environment

variable. The use of BSD-style options will also change the process

selection to include processes on other terminals (TTYs) that are owned

by you; alternately, this may be described as setting the selection to

be the set of all processes filtered to exclude processes owned by

other users or not on a terminal. These effects are not considered when

options are described as being "identical" below, so -M will be

20/04/2012 UNIX man pages : ps ()

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considered identical to Z and so on.

Except as described below, process selection options are additive. The

default selection is discarded, and then the selected processes are

added to the set of processes to be displayed. A process will thus be

shown if it meets any of the given selection criteria.

EXAMPLES

To see every process on the system using standard syntax:

ps -e

ps -ef

ps -eF

ps -ely

To see every process on the system using BSD syntax:

ps ax

ps axu

To print a process tree:

ps -ejH

ps axjf

To get info about threads:

ps -eLf

ps axms

To get security info:

ps -eo euser,ruser,suser,fuser,f,comm,label

ps axZ

ps -eM

To see every process running as root (real & effective ID) in user

format:

ps -U root -u root u

To see every process with a user-defined format:

ps -eo pid,tid,class,rtprio,ni,pri,psr,pcpu,stat,wchan:14,comm

ps axo stat,euid,ruid,tty,tpgid,sess,pgrp,ppid,pid,pcpu,comm

ps -eopid,tt,user,fname,tmout,f,wchan

Print only the process IDs of syslogd:ps -C syslogd -o pid=

Print only the name of PID 42:

ps -p 42 -o comm=

SIMPLE PROCESS SELECTION

-A Select all processes. Identical to -e.

-N Select all processes except those that fulfill the

specified conditions. (negates the selection) Identical

to --deselect.

T Select all processes associated with this terminal.




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This selects the processes whose effective user name or

ID is in userlist. The effective user ID describes the

user whose file access permissions are used by the

process (see geteuid(2)). Identical to -u and --user.

-U userlist select by real user ID (RUID) or name.

It selects the processes whose real user name or ID is

in the userlist list. The real user ID identifies the

user who created the process, see getuid(2).

-g grplist Select by session OR by effective group name.

Selection by session is specified by many standards,

but selection by effective group is the logical

behavior that several other operating systems use. This

ps will select by session when the list is completely

numeric (as sessions are). Group ID numbers will work

only when some group names are also specified. See the

-s and --group options.

p pidlist Select by process ID. Identical to -p and --pid.

-p pidlist Select by PID.

This selects the processes whose process ID numbers

appear in pidlist. Identical to p and --pid.

-s sesslist Select by session ID.

This selects the processes with a session ID specified

in sesslist.

t ttylist Select by tty. Nearly identical to -t and --tty, but

can also be used with an empty ttylist to indicate the

terminal associated with ps. Using the T option is

considered cleaner than using T with an empty ttylist.

-t ttylist Select by tty.

This selects the processes associated with the

terminals given in ttylist. Terminals (ttys, or screens

for text output) can be specified in several forms:

/dev/ttyS1, ttyS1, S1. A plain "-" may be used to

select processes not attached to any terminal.

-u userlist Select by effective user ID (EUID) or name.

This selects the processes whose effective user name or

ID is in userlist. The effective user ID describes the

user whose file access permissions are used by the

process (see geteuid(2)). Identical to U and --user.

--Group grplist Select by real group ID (RGID) or name. Identical to

-G.

--User userlist Select by real user ID (RUID) or name. Identical to -U.

--group grplist Select by effective group ID (EGID) or name.

This selects the processes whose effective group name

or ID is in grouplist. The effective group ID describes

the group whose file access permissions are used by theprocess (see geteuid(2)). The -g option is often an

alternative to --group.

--pid pidlist Select by process ID. Identical to -p and p.




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--ppid pidlist Select by parent process ID. This selects the processes

with a parent process ID in pidlist. That is, it

selects processes that are children of those listed in

pidlist.

--sid sesslist Select by session ID. Identical to -s.

--tty ttylist Select by terminal. Identical to -t and t.

--user userlist Select by effective user ID (EUID) or name. Identical

to -u and U.

-123 Identical to --sid 123.

123 Identical to --pid 123.

OUTPUT FORMAT CONTROL

These options are used to choose the information displayed by ps. Theoutput may differ by personality.

-F extra full format. See the -f option, which -F implies.

-O format is like -o, but preloaded with some default columns.

Identical to -o pid,format,state,tname,time,command or

-o pid,format,tname,time,cmd, see -o below.

O format is preloaded o (overloaded).

The BSD O option can act like -O (user-defined output

format with some common fields predefined) or can beused to specify sort order. Heuristics are used to

determine the behavior of this option. To ensure that

the desired behavior is obtained (sorting or

formatting), specify the option in some other way (e.g.

with -O or --sort). When used as a formatting option,

it is identical to -O, with the BSD personality.

-M Add a column of security data. Identical to Z.

(for SE Linux)

X Register format.

Z Add a column of security data. Identical to -M.

(for SE Linux)

-c Show different scheduler information for the -l option.

-f does full-format listing. This option can be combined

with many other UNIX-style options to add additional

columns. It also causes the command arguments to be

printed. When used with -L, the NLWP (number of

threads) and LWP (thread ID) columns will be added. See

the c option, the format keyword args, and the format

keyword comm.

j BSD job control format.

-j jobs format




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l display BSD long format.

-l long format. The -y option is often useful with this.

o format specify user-defined format. Identical to -o and

--format.

-o format user-defined format.

format is a single argument in the form of a

blank-separated or comma-separated list, which offers a

way to specify individual output columns. The

recognized keywords are described in the STANDARD

FORMAT SPECIFIERS section below. Headers may be renamed

(ps -o pid,ruser=RealUser -o comm=Command) as desired.

If all column headers are empty (ps -o pid= -o comm=)

then the header line will not be output. Column width

will increase as needed for wide headers; this may be

used to widen up columns such as WCHAN

(ps -o pid,wchan=WIDE-WCHAN-COLUMN -o comm). Explicit

width control (ps opid,wchan:42,cmd) is offered too.The behavior of ps -o pid=X,comm=Y varies with

personality; output may be one column named "X,comm=Y"

or two columns named "X" and "Y". Use multiple -o

options when in doubt. Use the PS_FORMAT environment

variable to specify a default as desired; DefSysV and

DefBSD are macros that may be used to choose the

default UNIX or BSD columns.

s display signal format

u display user-oriented format

v display virtual memory format

-y Do not show flags; show rss in place of addr. This

option can only be used with -l.

-Z display security context format (SELinux, etc.)

--format format user-defined format. Identical to -o and o.

--context Display security context format. (for SE Linux)

OUTPUT MODIFIERS

-H show process hierarchy (forest)

N namelist Specify namelist file. Identical to -n, see -n above.

O order Sorting order. (overloaded)

The BSD O option can act like -O (user-defined output

format with some common fields predefined) or can be

used to specify sort order. Heuristics are used to

determine the behavior of this option. To ensure that

the desired behavior is obtained (sorting or

formatting), specify the option in some other way (e.g.

with -O or --sort).




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For sorting, obsolete BSD O option syntax is

O[+|-]k1[,[+|-]k2[,...]]. It orders the processes

listing according to the multilevel sort specified by

the sequence of one-letter short keys k1, k2, ...

described in the OBSOLETE SORT KEYS section below.

The "+" is currently optional, merely re-iterating the

default direction on a key, but may help to distinguish

an O sort from an O format. The "-" reverses direction

only on the key it precedes.

S Sum up some information, such as CPU usage, from dead

child processes into their parent. This is useful for

examining a system where a parent process repeatedly

forks off short-lived children to do work.

c Show the true command name. This is derived from the

name of the executable file, rather than from the argv

value. Command arguments and any modifications to them

(see setproctitle(3)) are thus not shown. This option

effectively turns the args format keyword into the commformat keyword; it is useful with the -f format option

and with the various BSD-style format options, which

all normally display the command arguments. See the -f

option, the format keyword args, and the format keyword

comm.

e Show the environment after the command.

f ASCII-art process hierarchy (forest)

h No header. (or, one header per screen in the BSD

personality)The h option is problematic. Standard BSD ps uses this

option to print a header on each page of output, but

older Linux ps uses this option to totally disable the

header. This version of ps follows the Linux usage of

not printing the header unless the BSD personality has

been selected, in which case it prints a header on each

page of output. Regardless of the current personality,

you can use the long options --headers and --no-headers

to enable printing headers each page or disable headers

entirely, respectively.

k spec specify sorting order. Sorting syntax is

[+|-]key[,[+|-]key[,...]] Choose a multi-letter key

from the STANDARD FORMAT SPECIFIERS section. The "+" is

optional since default direction is increasing

numerical or lexicographic order. Identical to --sort.

Examples:

ps jaxkuid,-ppid,+pid

ps axk comm o comm,args

ps kstart_time -ef

-n namelist set namelist file. Identical to N.

The namelist file is needed for a proper WCHAN display,and must match the current Linux kernel exactly for

correct output. Without this option, the default search

path for the namelist is:

$PS_SYSMAP




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$PS_SYSTEM_MAP

/proc/*/wchan

/boot/System.map-`uname -r`

/boot/System.map

/lib/modules/`uname -r`/System.map

/usr/src/linux/System.map

/System.map

n Numeric output for WCHAN and USER. (including all types

of UID and GID)

-w Wide output. Use this option twice for unlimited width.

w Wide output. Use this option twice for unlimited width.

--cols n set screen width

--columns n set screen width

--cumulative include some dead child process data (as a sum with the

parent)

--forest ASCII art process tree

--headers repeat header lines, one per page of output

--no-headers print no header line at all

--lines n set screen height

--rows n set screen height

--sort spec specify sorting order. Sorting syntax is[+|-]key[,[+|-]key[,...]] Choose a multi-letter key

from the STANDARD FORMAT SPECIFIERS section. The "+" is

optional since default direction is increasing

numerical or lexicographic order. Identical to k. For

example: ps jax --sort=uid,-ppid,+pid

--width n set screen width

THREAD DISPLAY

H Show threads as if they were processes

-L Show threads, possibly with LWP and NLWP columns

-T Show threads, possibly with SPID column

m Show threads after processes

-m Show threads after processes

OTHER INFORMATION

L List all format specifiers.




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-V Print the procps version.

V Print the procps version.

--help Print a help message.

--info Print debugging info.

--version Print the procps version.

NOTES

This ps works by reading the virtual files in /proc. This ps does not

need to be setuid kmem or have any privileges to run. Do not give this

ps any special permissions.

This ps needs access to namelist data for proper WCHAN display. For

kernels prior to 2.6, the System.map file must be installed.

CPU usage is currently expressed as the percentage of time spent

running during the entire lifetime of a process. This is not ideal,

and it does not conform to the standards that ps otherwise conforms to.

CPU usage is unlikely to add up to exactly 100%.

The SIZE and RSS fields don't count some parts of a process including

the page tables, kernel stack, struct thread_info, and struct

task_struct. This is usually at least 20 KiB of memory that is always

resident. SIZE is the virtual size of the process (code+data+stack).

Processes marked are dead processes (so-called "zombies")

that remain because their parent has not destroyed them properly. These

processes will be destroyed by init(8) if the parent process exits.

If the length of the username is greater than the length of the display

column, the numeric user ID is displayed instead.

PROCESS FLAGS

The sum of these values is displayed in the "F" column, which is

provided by the flags output specifier.

1 forked but didn't exec

4 used super-user privileges

PROCESS STATE CODES

Here are the different values that the s, stat and state output

specifiers (header "STAT" or "S") will display to describe the state of

a process.

D Uninterruptible sleep (usually IO)

R Running or runnable (on run queue)

S Interruptible sleep (waiting for an event to complete)

T Stopped, either by a job control signal or because it is being




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.

W paging (not valid since the 2.6.xx kernel)

X dead (should never be seen)

Z Defunct ("zombie") process, terminated but not reaped by its

parent.

For BSD formats and when the stat keyword is used, additional

characters may be displayed:

< high-priority (not nice to other users)

N low-priority (nice to other users)L has pages locked into memory (for real-time and custom IO)

s is a session leader

l is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)

+ is in the foreground process group

OBSOLETE SORT KEYS

These keys are used by the BSD O option (when it is used for sorting).

The GNU --sort option doesn't use these keys, but the specifiers

described below in the STANDARD FORMAT SPECIFIERS section. Note that

the values used in sorting are the internal values ps uses and not the

"cooked" values used in some of the output format fields (e.g. sorting

on tty will sort into device number, not according to the terminal name

displayed). Pipe ps output into the sort(1) command if you want to sort

the cooked values.

KEY LONG DESCRIPTION

c cmd simple name of executable

C pcpu cpu utilization

f flags flags as in long format F field

g pgrp process group IDG tpgid controlling tty process group ID

j cutime cumulative user time

J cstime cumulative system time

k utime user time

m min_flt number of minor page faults

M maj_flt number of major page faults

n cmin_flt cumulative minor page faults

N cmaj_flt cumulative major page faults

o session session ID

p pid process ID

P ppid parent process ID

r rss resident set sizeR resident resident pages

s size memory size in kilobytes

S share amount of shared pages

t tty the device number of the controlling tty

T start_time time process was started

U uid user ID number

u user user name

v vsize total VM size in kB

y priority kernel scheduling priority

AIX FORMAT DESCRIPTORS

This ps supports AIX format descriptors, which work somewhat like the

formatting codes of printf(1) and printf(3). For example, the normal




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default output can be produced with this: ps -eo "%p %y %x %c".

The NORMAL codes are described in the next section.

CODE NORMAL HEADER

%C pcpu %CPU

%G group GROUP

%P ppid PPID

%U user USER

%a args COMMAND%c comm COMMAND

%g rgroup RGROUP

%n nice NI

%p pid PID

%r pgid PGID

%t etime ELAPSED

%u ruser RUSER

%x time TIME

%y tty TTY

%z vsz VSZ

STANDARD FORMAT SPECIFIERS

Here are the different keywords that may be used to control the output

format (e.g. with option -o) or to sort the selected processes with the

GNU-style --sort option.

For example: ps -eo pid,user,args --sort user

This version of ps tries to recognize most of the keywords used in

other implementations of ps.

The following user-defined format specifiers may contain spaces: args,

cmd, comm, command, fname, ucmd, ucomm, lstart, bsdstart, start.

Some keywords may not be available for sorting.

CODE HEADER DESCRIPTION

%cpu %CPU cpu utilization of the process in "##.#" format.

Currently, it is the CPU time used divided by the time the

process has been running (cputime/realtime ratio),

expressed as a percentage. It will not add up to 100%

unless you are lucky. (alias pcpu).

%mem %MEM ratio of the process's resident set size to the physical

memory on the machine, expressed as a percentage.

(alias pmem).

args COMMAND command with all its arguments as a string. Modifications

to the arguments may be shown. The output in this column

may contain spaces. A process marked is partly

dead, waiting to be fully destroyed by its parent.

Sometimes the process args will be unavailable; when thishappens, ps will instead print the executable name in

brackets. (alias cmd, command). See also the comm format

keyword, the -f option, and the c option.

When specified last, this column will extend to the edge

of the display. If ps can not determine display width, as




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when output is redirected (piped) into a file or another

command, the output width is undefined. (it may be 80,

unlimited, determined by the TERM variable, and so on) The

COLUMNS environment variable or --cols option may be used

to exactly determine the width in this case. The w or -w

option may be also be used to adjust width.

blocked BLOCKED mask of the blocked signals, see signal(7). According to

the width of the field, a 32-bit or 64-bit mask inhexadecimal format is displayed.

(alias sig_block, sigmask).

bsdstart START time the command started. If the process was started less

than 24 hours ago, the output format is " HH:MM", else it

is "mmm dd" (where mmm is the three letters of the month).

bsdtime TIME accumulated cpu time, user + system. The display format is

usually "MMM:SS", but can be shifted to the right if the

process used more than 999 minutes of cpu time.

c C processor utilization. Currently, this is the integervalue of the percent usage over the lifetime of the

process. (see %cpu).

caught CAUGHT mask of the caught signals, see signal(7). According to

the width of the field, a 32 or 64 bits mask in

hexadecimal format is displayed.

(alias sig_catch, sigcatch).

class CLS scheduling class of the process. (alias policy, cls).

Field's possible values are:

- not reportedTS SCHED_OTHER

FF SCHED_FIFO

RR SCHED_RR

? unknown value

cls CLS scheduling class of the process. (alias policy, class).

Field's possible values are:

- not reported

TS SCHED_OTHER

FF SCHED_FIFO

RR SCHED_RR

? unknown value

cmd CMD see args. (alias args, command).

comm COMMAND command name (only the executable name). Modifications to

the command name will not be shown. A process marked

is partly dead, waiting to be fully destroyed by

its parent. The output in this column may contain spaces.

(alias ucmd, ucomm). See also the args format keyword, the

-f option, and the c option.

When specified last, this column will extend to the edge

of the display. If ps can not determine display width, as

when output is redirected (piped) into a file or another

command, the output width is undefined. (it may be 80,

unlimited, determined by the TERM variable, and so on) The

COLUMNS environment variable or --cols option may be used

to exactly determine the width in this case. The w or -w




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.

command COMMAND see args. (alias args, cmd).

cp CP per-mill (tenths of a percent) CPU usage. (see %cpu).

cputime TIME cumulative CPU time, "[dd-]hh:mm:ss" format. (alias time).

egid EGID effective group ID number of the process as a decimal

integer. (alias gid).

egroup EGROUP effective group ID of the process. This will be the

textual group ID, if it can be obtained and the field

width permits, or a decimal representation otherwise.

(alias group).

eip EIP instruction pointer.

esp ESP stack pointer.

etime ELAPSED elapsed time since the process was started, in the

form [[dd-]hh:]mm:ss.

euid EUID effective user ID. (alias uid).

euser EUSER effective user name. This will be the textual user ID,

if it can be obtained and the field width permits,

or a decimal representation otherwise. The n option can be

used to force the decimal representation.

(alias uname, user).

f F flags associated with the process, see the PROCESS FLAGS

section. (alias flag, flags).

fgid FGID filesystem access group ID. (alias fsgid).

fgroup FGROUP filesystem access group ID. This will be the textual

user ID, if it can be obtained and the field width

permits, or a decimal representation otherwise.

(alias fsgroup).

flag F see f. (alias f, flags).

flags F see f. (alias f, flag).

fname COMMAND first 8 bytes of the base name of the process's executable

file. The output in this column may contain spaces.

fuid FUID filesystem access user ID. (alias fsuid).

fuser FUSER filesystem access user ID. This will be the textual

user ID, if it can be obtained and the field width

permits, or a decimal representation otherwise.

gid GID see egid. (alias egid).

group GROUP see egroup. (alias egroup).

ignored IGNORED mask of the ignored signals, see signal(7). According to

the width of the field, a 32-bit or 64-bit mask in

hexadecimal format is displayed. (alias sig_ignore,




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.

label LABEL security label, most commonly used for SE Linux context

data. This is for the Mandatory Access Control ("MAC")

found on high-security systems.

lstart STARTED time the command started.

lwp LWP lwp (light weight process, or thread) ID of the lwp being

reported. (alias spid, tid).

ni NI nice value. This ranges from 19 (nicest) to -20 (not nice

to others), see nice(1). (alias nice).

nice NI see ni. (alias ni).

nlwp NLWP number of lwps (threads) in the process. (alias thcount).

nwchan WCHAN address of the kernel function where the process is

sleeping (use wchan if you want the kernel function name).

Running tasks will display a dash ('-') in this column.

pcpu %CPU see %cpu. (alias %cpu).

pending PENDING mask of the pending signals. See signal(7). Signals

pending on the process are distinct from signals pending

on individual threads. Use the m option or the -m option

to see both. According to the width of the field, a 32-bit

or 64-bit mask in hexadecimal format is displayed.

(alias sig).

pgid PGID process group ID or, equivalently, the process ID of the

process group leader. (alias pgrp).

pgrp PGRP see pgid. (alias pgid).

pid PID process ID number of the process.

pmem %MEM see %mem. (alias %mem).

policy POL scheduling class of the process. (alias class, cls).

Possible values are:

- not reported

TS SCHED_OTHER

FF SCHED_FIFORR SCHED_RR

? unknown value

ppid PPID parent process ID.

psr PSR processor that process is currently assigned to.

rgid RGID real group ID.

rgroup RGROUP real group name. This will be the textual group ID, if it

can be obtained and the field width permits, or a decimal

representation otherwise.

rss RSS resident set size, the non-swapped physical memory that a

task has used (in kiloBytes). (alias rssize, rsz).




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. , .

rsz RSZ see rss. (alias rss, rssize).

rtprio RTPRIO realtime priority.

ruid RUID real user ID.

ruser RUSER real user ID. This will be the textual user ID, if it can

be obtained and the field width permits, or a decimalrepresentation otherwise.

s S minimal state display (one character). See section PROCESS

STATE CODES for the different values. See also stat if you

want additional information displayed. (alias state).

sched SCH scheduling policy of the process. The policies

sched_other, sched_fifo, and sched_rr are respectively

displayed as 0, 1, and 2.

sess SESS session ID or, equivalently, the process ID of the

session leader. (alias session, sid).

sgi_p P processor that the process is currently executing on.

Displays "*" if the process is not currently running or

runnable.

sgid SGID saved group ID. (alias svgid).

sgroup SGROUP saved group name. This will be the textual group ID, if it


representation otherwise.

sid SID see sess. (alias sess, session).

sig PENDING see pending. (alias pending, sig_pend).

sigcatch CAUGHT see caught. (alias caught, sig_catch).

sigignore IGNORED see ignored. (alias ignored, sig_ignore).

sigmask BLOCKED see blocked. (alias blocked, sig_block).

size SZ approximate amount of swap space that would be required if

the process were to dirty all writable pages and then beswapped out. This number is very rough!

spid SPID see lwp. (alias lwp, tid).

stackp STACKP address of the bottom (start) of stack for the process.

start STARTED time the command started. If the process was started less

than 24 hours ago, the output format is "HH:MM:SS", else

it is " mmm dd" (where mmm is a three-letter month name).

start_time START starting time or date of the process. Only the year will

be displayed if the process was not started the same year

ps was invoked, or "mmmdd" if it was not started the same

day, or "HH:MM" otherwise.

stat STAT multi-character process state. See section PROCESS STATE




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.

state if you just want the first character displayed.

state S see s. (alias s).

suid SUID saved user ID. (alias svuid).

suser SUSER saved user name. This will be the textual user ID, if it


representation otherwise. (alias svuser).

svgid SVGID see sgid. (alias sgid).

svuid SVUID see suid. (alias suid).

sz SZ size in physical pages of the core image of the process.

This includes text, data, and stack space. Device mappings

are currently excluded; this is subject to change. See vsz

and rss.

thcount THCNT see nlwp. (alias nlwp). number of kernel threads owned by

the process.

tid TID see lwp. (alias lwp).

time TIME cumulative CPU time, "[dd-]hh:mm:ss" format.

(alias cputime).

tname TTY controlling tty (terminal). (alias tt, tty).

tpgid TPGID ID of the foreground process group on the tty (terminal)

that the process is connected to, or -1 if the process is

not connected to a tty.

tt TT controlling tty (terminal). (alias tname, tty).

tty TT controlling tty (terminal). (alias tname, tt).

ucmd CMD see comm. (alias comm, ucomm).

ucomm COMMAND see comm. (alias comm, ucmd).

uid UID see euid. (alias euid).

uname USER see euser. (alias euser, user).

user USER see euser. (alias euser, uname).

vsize VSZ see vsz. (alias vsz).

vsz VSZ virtual memory size of the process in KiB

(1024-byte units). Device mappings are currently excluded;

this is subject to change. (alias vsize).

wchan WCHAN name of the kernel function in which the process is

sleeping, a "-" if the process is running, or a "*" if theprocess is multi-threaded and ps is not displaying

threads.

ENVIRONMENT VARIABLES




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The following environment variables could affect ps:

COLUMNS

Override default display width.

LINES

Override default display height.

PS_PERSONALITY

Set to one of posix, old, linux, bsd, sun, digital...

(see section PERSONALITY below).

CMD_ENV

Set to one of posix, old, linux, bsd, sun, digital...

(see section PERSONALITY below).

I_WANT_A_BROKEN_PS

Force obsolete command line interpretation.

LC_TIME

Date format.

PS_COLORS

Not currently supported.

PS_FORMAT

Default output format override. You may set this to a format string

of the type used for the -o option. The DefSysV and DefBSD values

are particularly useful.

PS_SYSMAPDefault namelist (System.map) location.

PS_SYSTEM_MAP

Default namelist (System.map) location.

POSIXLY_CORRECT

Don't find excuses to ignore bad "features".

POSIX2

When set to "on", acts as POSIXLY_CORRECT.

UNIX95Don't find excuses to ignore bad "features".

_XPG

Cancel CMD_ENV=irix non-standard behavior.

In general, it is a bad idea to set these variables. The one exception

is CMD_ENV or PS_PERSONALITY, which could be set to Linux for normal

systems. Without that setting, ps follows the useless and bad parts of

the Unix98 standard.

PERSONALITY

390 like the S/390 OpenEdition ps

aix like AIX ps




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bsd like FreeBSD ps (totally non-standard)

compaq like Digital Unix ps

debian like the old Debian ps

digital like Tru64 (was Digital Unix, was OSF/1) ps

gnu like the old Debian ps

hp like HP-UX ps

hpux like HP-UX ps

irix like Irix ps

linux ***** RECOMMENDED *****old like the original Linux ps (totally non-standard)

os390 like OS/390 Open Edition ps

posix standard

s390 like OS/390 Open Edition ps

sco like SCO ps

sgi like Irix ps

solaris2 like Solaris 2+ (SunOS 5) ps

sunos4 like SunOS 4 (Solaris 1) ps (totally non-standard)

svr4 standard

sysv standard

tru64 like Tru64 (was Digital Unix, was OSF/1) ps

unix standard

unix95 standard

unix98 standard

SEE ALSO

top(1), pgrep(1), pstree(1), proc(5).

STANDARDS

This ps conforms to:

1 Version 2 of the Single Unix Specification

2 The Open Group Technical Standard Base Specifications, Issue 6

3 IEEE Std 1003.1, 2004 Edition

4 X/Open System Interfaces Extension [UP XSI]

5 ISO/IEC 9945:2003

AUTHOR

ps was originally written by Branko Lankester .

Michael K. Johnson re-wrote it significantly to

use the proc filesystem, changing a few things in the process. Michael

Shields added the pid-list feature. Charles

Blake added multi-level sorting, the dirent-style

library, the device name-to-number mmaped database, the approximate

binary search directly on System.map, and many code and documentation

cleanups. David Mossberger-Tang wrote the generic BFD support forpsupdate. Albert Cahalan rewrote ps for full

Unix98 and BSD support, along with some ugly hacks for obsolete and

foreign syntax.

Please send bug reports to .




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No subscription is required or suggested.

Linux July 28, 2004 PS(1)

1994Man-cgi 1.15, Panagiotis Christias


Documents

UNIX Man Pages _ Ps ()